Systemic-onset juvenile idiopathic arthritis (JIA)

Systemic-onset juvenile idiopathic arthritis affects children and young people. In this form of arthritis, joint pain is part of a general illness involving fever, tiredness, rash, loss of appetite and weight loss.

• You may have enlarged glands in your neck, under your arms and around your groin area. Your doctor may find your spleen and liver are enlarged, and, very occasionally, the covering of the heart is inflamed (pericarditis).
• In the first few weeks there may be no sign of swollen joints, and the diagnosis may be uncertain. Lots of tests may be needed to confirm the diagnosis and this can be a worrying time.
• The long-term development of this form of JIA can be difficult to predict but usually the fever and rash will settle, although the arthritis may sometimes continue for several years before settling.